1. Field of the Invention
The present invention relates to a buckle, and more particularly, to a buckle having a plug member and a socket member which are mounted to the free ends of belts or straps attached to various articles such as clothes, knapsacks and helmets and are detachably coupled to each other.
2. Description of the Related Art
In general, a buckle serves as a locker in which a plug member and a socket member are detachably coupled to each other to allow the length of a belt or a strap to be adjusted so as to fit the human body or fix a product. The buckle as a locker is formed of a plastic material so that the plug member and the socket member can be elastically coupled to each other.
FIG. 1 is a schematic exploded perspective view illustrating a conventional buckle. The buckle includes a plug member 10 and a socket member 20.
As shown in FIG. 1, the plug member 10 has a pair of lock arms 12 which project straight forward from a base part 11 constituting a body of the plug member 10 and possess a predetermined degree of elasticity. Locking parts are projectedly formed on the outer surfaces of the distal end portions of the respective lock arms 12. A guide rod 13 is formed between the lock arms 12 to extend straight forward from the base part 11. The socket member 20 defines a chamber 21 which is open at the distal end of the socket member 20, so that the plug member 10 can be received into the chamber 21. A pair, of openings 22 are oppositely defined on both sidewalls of the socket member 20 so that the locking parts of the lock arms 12 can be elastically engaged into the openings 22.
As a user inserts the plug member 10 through the distal entrance of the socket member 20 into the chamber 21, the outer surfaces of the pair of lock arms 12, which are formed on both sides of the plug member 10, slide on the inner surfaces of the sidewalls of the socket member 20 while being elastically bent inward. Then, as the locking parts formed on the distal end portions of the lock arms 12 are aligned with the pair of openings 22, the locking parts if the lock arms 12 are elastically engaged into the openings 22 so that the plug member 10 and the socket member 20 are completely coupled to each other.
Thereafter, when it is necessary to decouple the buckle, the locking parts of the lock arms 12 of the plug member 10, which are exposed through the openings 22 of the socket member 20, are pressed from both outsides such that the respective locking parts of the lock arms 12 are disengaged from the openings 22 of the socket member 20. Then, as the plug member 10 is pulled outside, the plug member 10 and the socket member 20 are decoupled from each other.
However, in the conventional buckle, in order to allow the locking parts of the lock arms 12 to be stably engaged into the openings 22 of the socket member 20, the elastic stiffness of the lock arms 12 is increased. Due to this fact, when the lock arms 12 are excessively bent outward, problems are caused in that the lock arms 12 are likely to be deformed or broken. Also, since the lock arms 12 can be bent outward by being hooked by an object or by mistake while in use, the lock arms 12 can be easily damaged by the erroneous manipulation.
Further, in the conventional buckle, foreign substances can be easily attached in the socket member 20 or around the lock arms 12, and it is difficult to remove the foreign substances. Due to this fact, difficulties exist in appropriately manipulating the buckle, and poor coupling of the plug member 10 and the socket member 20 can result.
A structure in which lock arms are connected to bridges so as to prevent the deformation of the lock arms has been disclosed in Korean Patent No. 10-0467922. The inner surfaces of the lock arms are connected to a guide rod by the bridges. Nevertheless, in this structure, while the excessive outward bending of the lock arms can be prevented, the elasticity of the lock arms is unduly limited in the lateral direction. Consequently, inconvenience is caused when coupling and decoupling a plug member and a socket member to and from each other, and elastic shock increases upon coupling the plug member and the socket member to each other.
Another structure in which lock arms are connected by a bridge so as to prevent the excessive outward bending of the lock arms has been disclosed in Korean Patent No. 10-0601259. In a construction of directly connecting the lock arms by the bridge, the bridge has a shape which surrounds the outer surface of a guide rod.
Nonetheless, even in this structure, since the elasticity of the lock arms is unduly limited in the lateral direction, inconvenience is caused when coupling and decoupling a plug member and a socket member to and from each other. Further, a problem is caused in that the function of the guide rod for guiding the smooth coupling of the plug member and the socket member is likely to be lost.
As a result, the conventional buckles suffer from defects in that it is inappropriate to prevent the excessive outward bending of the lock arms while maintaining the sufficient elasticity of the lock arms, foreign substances can be easily attached in the socket member, and it is difficult to remove the foreign substances.